1. Field of the Invention
The present invention relates generally to needle array devices and methods of fabrication.
2. Related Art
The potential for implanting electronic devices into patients with direct interface to the neural system is vast. Systems which may enable paraplegics to regain control of their bladder or limbs, provide vision for the blind, or restore vocal cord function are all under development, and promising initial results have been obtained in some experiments.
A key component of some implantable systems is a needle array to enable interfacing of the electronics with a neuron or directly into brain tissue. For example, U.S. Pat. No. 5,215,088 to Normann et al. discloses a three-dimensional electrode device which can be used as a neural or cortical implant. The device of Norman, also known as the Utah Electrode Array (UEA), can be used to provide a neural interface to electronic equipment for sensing and/or stimulation. Alternative approaches for fabricating similar devices are known, but require a large number of masking steps which also slows down production and increases cost of manufacture.
While the UEA has been in experimental use for a number of years, fabrication techniques have been relatively unrefined. Fortunately, demand for the UEA has been limited to experimental use, so few devices are needed. With greater experimental usage, and the eventual possibility for production level requirements, existing fabrication techniques may provide inadequate quality, repeatability, and throughput.